/** Function from <http://en.wikipedia.org/wiki/Integral>.  Integral from
 *  -2 to +2 is 3.76.
 */
double 
wikipediaFn(double x) 
{
  return 0.2 * (0.01*(322 + 3*x*(98 + x * (37 + x))) - 24*x/(1 + x*x));
}
